This invention relates to an improvement of a torque transfer mechanism used exclusively on a socket wrench. The prior art socket wrench constitutes an integrally formed handle, a wrench head and a shank. The wrench head has a vertical housing cavity to receive a torque head. A ratchet and a pair of finger-operated brake drums are outfitted in the housing wall with an adjusting knob located on the top of the torque head, permitting the torque head to carry out a right turn or a left turn, as desired, to tighten and loosen a bolt. The torque input comes from swinging the handle of the socket wrench, and the torque output is vertically applied to the bolt. However, when tightening or loosening the blot, the handle of the socket wrench must be placed perpendicular to the bolt. But in the reciprocated swing, it is very hard for the operator to keep the handle level; in other words, the swing usually results in an up and down oscillation. This oscillation produces unstable contact of the torque head with the bolt in the square recess, as well as an unstabilized torque output. When the bolt does not reach a depth to obtain an adequate holding force, and when the handle is returned for the next turning, the bolt will follow the torque head to return simultaneously to its prior position with no resistance. This is an obvious hardship encountered at the very beginning of a bolt tightening operation. In other cases, the longer the bolt shank the more difficult it will be to maintain a level swing together with a vertical and accurate contact with the bolt. This shortfall causes consumers to dislike using the prior art socket wrench. It is necessary to carry out an improvement on the prior art socket wrench and this is the goal the invention strikes for.
The object of the invention is to provide an improved torque transfer mechanism for a socket wrench where the shank of the socket wrench contains a torque head inside of a hollow body. The front end of the torque head is locked on a ring gear which meshes with a bevel gear to form a torque transfer mechanism. The torque transfer mechanism of the invention is robust, easy to assemble and the torque output is stable to enhance easy tightening operation of the bolt.
Another object of the invention is provide an improved torque transfer mechanism for the part art of the socket wrench even without any modification in its construction. It is easy to fabricate, assemble, and operate with minor additions of new parts.